JPS6315648A - Structure of bracket for motor - Google Patents

Abstract

PURPOSE:To prevent resin form blowing to the outside circumference of a faucet section, by keeping the clearance as required between the outside circumference of the faucet section and a mold when the resin is integrally molded into a bracket. CONSTITUTION:A recessed resin inserting section 6c of a front bracket 6 is formed so as to keep a wide large clearance beta from a faucet section 6a to the outside surface of an end face section 6b where the faucet section 6a projects. On this account, if a mold 10 is put over to the outside circumference of the front bracket 6, the tip of the mold is brought into contact with the outside surface of the end face section 6b in the state where the desired clearance alpha can be kept between the mold 10 and the outside circumference of the faucet section 6a. Thus, the clearance alpha between the faucet section 6a and the mold 10 can be made in the state where the resin flow is entirely blocked, so that the resin material 9 can be prevented from flowing into the faucet section 6a.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a bracket structure for an electric motor such as a starter motor.

[Problems to be solved by the prior art and the invention] In general, some electric motors of this type have a pilot part protruding from a bracket such as a front bracket, and the pilot part is inserted into the side of the engine or the like to which it is attached. As for attachment, there is one in which a resin member such as a brush holder is integrally attached to the bracket by molding. However, conventionally, when molding a resin material into a bracket, a flat bracket 1 as shown in FIG.
The mold 13 was placed on the end surface of the mold 13, and the resin material was poured there.In this case, the mold 13
It is necessary to provide a slight clearance α between the outer circumferential surface of the spigot part 12a and the outer peripheral surface of the spigot part 12a in order to eliminate the galling phenomenon caused by the mold and to accommodate variations in the dimensions of the spigot part. For this reason, the resin material inevitably enters the clearance area, and as a result, after molding,
This requires post-processing work to remove the resin material that has flowed around the outer periphery of the spigot part, resulting in a disadvantage in that the workability is extremely poor, and the process is interlayered.

[Means for Solving the Problems] In view of the above-mentioned circumstances, the present invention was devised for the purpose of providing a bracket structure for an electric motor that can eliminate these drawbacks. In this electric motor, a spigot part that is fitted into the side of the bracket to be mounted protrudes, and a resin material is molded on the end face of the bracket. The present invention is characterized in that a concave resin insertion portion is formed in a state where a clearance larger than the clearance between the two is secured, and a resin material is molded into the resin insertion portion.

With this configuration, when integrally molding the resin material into the bracket, the present invention can secure the required clearance between the outer periphery of the pilot part and the mold, while also preventing the flow of resin to the outer periphery of the pilot part. This is to ensure that this can be prevented.

[Embodiment] Next, an embodiment of the present invention will be described based on the drawings. In the drawings, reference numeral 1 denotes a small starter motor installed in a traveling vehicle such as a motorcycle, and the starter motor 1 includes:
A rotor 3 and a permanent magnet 4 are installed in the yoke 2 so that they can be moved freely.
, brush 5, etc. are all the same as before.

Reference numeral 6 denotes a front bracket that is integrally attached to the yoke 2 using screws 7, and the front bracket 6 has a pilot part 6a formed in its center that projects outward in the axial direction of the rotor 3. One end of the rotor shaft 3a is rotatably supported by a bearing 7a fitted to the inner peripheral surface of the spigot part 6a. Reference numeral 8 denotes a brush holder for accommodating the brush 5, and the brush 5 housed in the brush holder 8 is always projected by a bullet 5a and is brought into pressure contact with the commutator '3b of the rotor 3. However, this brush holder 8 is formed by integrally molding a resin material 9 onto the front bracket 6 by molding. That is, the end surface part 6b of the front bracket 6 has an outer surface, which is the side from which the spigot part 6a protrudes, which is formed by molding l.
A concave resin insertion portion 6c is formed such that a clearance β larger than the required clearance α is secured between O and the outer peripheral surface of the spigot portion 6a. and resin material 9
When molding, on the outer surface side, as described above, the mold lO is placed so that the tip part contacts the outer surface of the end face part 6b while ensuring a clearance α between it and the outer periphery of the spigot part 6a. , it will be molded in this state.

In this state, the toilet fat insertion part 6c is separated from the clearance α on the spigot part side by the mold 10 that is in contact with the outer surface of the end face part 6b, so that the resin material 9 is On the side, the resin flows into the resin insertion part 6c and is molded in a substantially flat state with the outer surface of the end face part.

In the embodiment constructed as described above, the resin material 9 is integrally molded on the front bracket 6.

All you have to do is apply the mold lO to the front bracket 6 from the inside and outside, pour the resin material 9 here, and mold it.
In this case, the resin material 9 does not flow into the outer periphery of the spigot part 6a of the front bracket 6. In other words, in the present invention, the resin material 9 has a concave shape on the outer surface of the end face part 6b from which the spigot part 6a of the front bracket 6 projects. The insertion portion 6c is
It is formed to have a wide clearance β from the spigot part 6a. For this reason, mold type 10
If it is applied to the outside of the front bracket 6, the tip of the mold will come into contact with the outer surface of the end face part 6b while the desired clearance α is secured between the mold 10 and the outer peripheral surface of the spigot part 6a. I will do it. Therefore, the clearance α between the spigot part 6a and the mold 10 can be completely closed off from the flow of the resin, thereby reliably preventing problems such as the resin material 9 flowing into the spigot part 6a. It will be possible. Furthermore, the clearance α between the spigot part 6a and the mold 10 can be freely set within a range that does not exceed the clearance β, and therefore a great degree of freedom can be secured for variations in the outer diameter of the spigot part 6a. It is also possible to eliminate the galling phenomenon with the mold.

Moreover, in the present invention, when the spigot part 6a is fitted and installed on the engine E side, which is the part to be installed, the spigot part 6a
It is necessary to fit the O-ring 11 into the root part of the bracket to ensure waterproofness. At the outer surface of the engine E
As a result, the amount of deformation of the ○-ring 11 can be made almost uniform, and it is also possible to eliminate variations in waterproofness between products, thereby achieving high quality. This will enable a stable supply of products.

It should be noted that the present invention is of course not limited to the above-mentioned embodiments, and the electric motor is not limited to a starter motor, but may be any type having a spigot part fitted to a bracket. Needless to say, this method is applicable not only to brackets but also to rear brackets.

[Operations and Effects] In summary, since the present invention is constructed as described above, when molding the resin material on the bracket I-, the mold is used on the outer surface of the bracket to maintain the required clearance with the outer periphery of the spigot part. The tip can be set in such a way that it comes into contact with the outer surface of the end face of the bracket in a state where A structure can be created that is closed from the flow of the resin material by the abutting portion, and it is possible to reliably prevent problems such as the resin material flowing to the outer periphery of the spigot part as in the conventional case. Moreover, when installing this product by fitting the spigot part into the side of the part to be installed, when fitting the 0-ring into the spigot part to ensure waterproofness, the 0-ring is made of resin at a part of the corner of the spigot part. It is crushed by the outer surface of the end face of the bracket, which is approximately flat with the surface, so that the amount of crushing of the 〇-ring can be made approximately equal, and it is possible to eliminate variations in waterproofness between products. This means that we can provide a stable supply of high-quality products.

[Brief explanation of the drawing]

The drawings show an embodiment of the bracket structure of an electric motor according to the present invention, in which Fig. 1 is a longitudinal sectional view of the starter motor, Fig. 2 is a front view of the front bracket, and Fig. 3 is an enlarged sectional view of the same. FIG. 4 is an explanatory view of the operation showing the state of molding, FIG. 5 is a sectional view of a main part showing the state of assembly to the engine, and FIG. 6 is an explanatory view of the operation showing the state of conventional molding. In the figure, 1 is the starter motor, 6 is the front bracket,
6a spigot part, 6b end face part, 6C resin insertion part, 9
1 is a resin material, and 10 is a mold type. Patent applicant Mitsuba Electric Manufacturing Co., Ltd. Figure 3 Figure 4 Figure 5 2a

Claims (1)

[Claims] In an electric motor in which a bracket such as a front bracket is provided with a spigot part that fits into the side to be mounted, and a resin material is molded on the end face of the bracket, the spigot part and the mold are formed on the side surface of the spigot part of the bracket end face. A bracket structure for an electric motor, characterized in that a concave resin insertion part is formed with a clearance larger than the clearance between the bracket and the mold, and a resin material is molded into the resin insertion part.